Legal immigrants who use public benefits - such as Medicaid, food stamps or housing assistance - could have a tougher time obtaining a green card or U.S. citizenship under a policy change announced Monday that is at the center of the Trump administration's effort to reduce immigration.

The new policy for "Inadmissibility on Public Charge Grounds," which appeared Monday on the Federal Register's website and will take effect in two months, sets new standards for obtaining permanent residency and U.S. citizenship. The Trump administration has been seeking to limit those immigrants who might draw on taxpayer-funded benefits, such as many of those who have been fleeing Central America, while allowing more highly skilled and wealthy immigrants into the United States.

Wealth, education, age and English-language skills will take on greater importance in the process for obtaining a green card, as the change seeks to redefine what it means to be a "public charge," as well as who is likely to be one under U.S. immigration law.

Analysts say the policy could dramatically reduce family-based legal immigration to the United States, particularly from Mexico, Central America and Africa, where economies have been suffering and incomes are lower.

The rule effectively circumvents earlier, failed efforts by the administration to build support in Congress for a similar "merit-based" overhaul to the immigrant visa system, and fulfills a longtime goal of senior Trump adviser Stephen Miller and other immigration hawks who have long sought new bureaucratic tools to reduce immigration levels.

The new rule - from U.S. Citizenship and Immigration Services, an agency within the Department of Homeland Security - focuses on the obscure definition of what it means to be a "public charge," or someone dependent of U.S. government benefits, and who is "likely" to become one.

Likeliness of becoming a public charge already is grounds to be denied a green card or the opportunity to become a U.S. citizen.

The Trump administration will broaden the public charge definition to encompass not just those primarily dependent on public assistance programs, but anyone who uses a public benefit, including publicly funded health care programs including Medicaid, food stamps, other nutrition-related programs, or housing assistance.

The New York mayor's Office and immigration think tanks say just the anticipation of that provision already has caused large numbers of legal immigrants to abstain from seeking help through such programs - despite being legally entitled to do so - because they are afraid it will hinder their ability to become citizens or remain in the United States.

But the new rule stands to have its most dramatic impact on the numbers and demographics of those permitted to immigrate to the United States through a vast array of new criteria to assess whether an individual is "likely" to someday become a public charge.

Factors that can count against a green card applicant include having "a medical condition" that will interfere with work or school; not having enough money to cover "any reasonably foreseeable medical costs" related to such a medical condition; having "financial liabilities;" having been approved to receive a public benefit, even if the individual has not actually received the benefit; having a low credit score; the absence of private health insurance; the absence of a college degree; not having the English language skills "sufficient to enter the job market;" or having a sponsor who is "unlikely" to provide financial support.

"With one regulation, they are attempting to scratch two itches: one is penalizing immigrants for using public benefits that they are legally entitled to, and the other is cutting legal immigration in half," said Doug Rand, a former Obama administration official and an immigration consultant. "And the way you cut legal immigration in half is by kicking the doors out from the definition of 'likely to become a public charge.'"

Trump has on multiple occasions alluded to the types of people that he would like to keep from coming to the United States (Africans, Haitians, Muslims, Central Americans, etc.), and those he would like to see more of (Norwegians), drawing frequent allegations of overt racism from Democrats and some Republicans.

Immigration advocates expect the rule to draw an immediate flurry of lawsuits.

Marielena Hincapie, of the National Immigration Law Center, described the proposed policy change as "President Trump's attempts to fundamentally transform our immigration system to favor the wealthy."

Forty-four House Democrats in June co-sponsored a bill to try to block the rule as it was being developed.

Under U.S. law, legal permanent residents who have had green cards for at least five years are eligible to apply for public benefits.

But in New York City, where nearly 20% of the population relies on SNAP benefits to help feed their families, officials have found that twice as many "eligible noncitizen New Yorkers are either withdrawing from or not enrolling in SNAP" than eligible U.S. citizens, particularly in the past two years as rumors of the coming public charge rule have circulated, according to an analysis by the New York City Department of Social Services and the Mayor's Office of Immigrant Affairs.

“While we cannot definitively prove that the public charge proposal has caused these changes to SNAP participation, we identify an important correlation that, reinforced by anecdotal and survey evidence, suggests a chilling effect: eligible immigrant families are avoiding SNAP out of fear of potential immigration consequences,” city officials wrote in the June analysis.